talking loudly in a foreign language is best avoided as it creates a clear barrier between locals and visitors - a sense of 'us' and 'them' - which runs contrary to the philosophy of cultural sharing and learning that underpins favela visits. 

understanding carioca culture in general is beneficial -  for instance, soccer is extremely popular in rio de janeiro, thus avoiding wearing t-shirts of adversaries soccer teams is appreciated and seen as a polite gesture.

ideally, visitors should learn a few basic words before going into a visit - such as 'bom dia,' meaning good-day, 'oi,' meaning 'hi,' and most importantly 'obrigado,' meaning 'thank you' - a word that should be used whenever possible to show gratitude to the hospitality.

the proper interaction between visitors and residents results in a more rewarding cultural exchange between both groups, and an ever more welcoming and favorable attitude towards favela visits in general.